Underlying the furor surrounding the use of illicitly obtained Facebook data in the 2016 presidential campaign is the rise of what one expert calls “mass micro persuasion.” Campaigns are growing ever more sophisticated in sifting vast amounts of social media and voting data to tailor political messages to individuals.

Source: New concern in social media age: profiling as a threat to democracy
“mass micro persuasion” – propaganda used to be messaging directed to groups to persuade all to adopt someone else’s agenda. With social media, we can direct propaganda crafted to the individual.